A display device includes wirings such as data signal lines and gate signal lines, and thin film transistors. The display device further includes source drivers supplying data signal with the data signal lines and gate drivers supplying gate signal with the gate signal lines.
Recently, in a narrow bezel technology, source drivers and gate drivers are mounted on only one edge of the display device in order to obtain a narrow bezel (see, unexamined patent publication JP2008-501138A1).
In the narrow bezel technology, the display device further includes gate lead lines extending in the column direction so as to electrically connect the gate drivers to the gate signal lines respectively. The gate lead lines are connected to the gate signal lines through contact holes respectively.